On the Sunday 10th of March 2019 Nairobi-bound Boeing 737MAX8 Flight ET302 of EthiopianAirlines plunge in to the ground and kills all 157 passengers onboard. Consequently, the accidenttook attention of international media and people around the world. This study therefore aims atinvestigating the communication strategies employed by EAL when managing ET302 planecrash and various issues associated with the crash using the two stages of crisis management. Toachieve the purpose, Nethnography and CDA methods were employed. To analyze thecommunication strategies SCCT was used. Accordingly, it was found out that, EAL highlyapplied “apology”, “shifting blame”, and “corrective action” strategies in its crisiscommunication via Facebook and Twitter pages. Additionally, the fairly immediate responsesgiven to each issue, the media monitoring system and the empathetic approach contributed to thegood crisis management. The study also finds out that more attention was given to the Twitterand updates were faster than the Facebook page. The study concludes that previous good imageof EAL plays a significant role to the impact a crisis would have in addition to its effective crisismanagement via social media. Finally, it’s recommended that EAL should communicate moreefficiently on its Facebook page to uplift its accomplishments and meet its online publics in awide range.

How and what companies publishes on social media have become more important. Different types of post generate different type of effects and if companies want to create brand loyalty and brand trust they must take this in consideration. Consumers want to be reached by content that is personal, they also want to feel that the companies deliver something of value. Content marketing deals with this aspect and focus on helping, informing and entertaining the recipients. This study examines informative, personal and entertaining posts and how they affect brand trust and brand loyalty. A quantitative method have been used in this study and a survey was used to gather data. 150 respondents answered the survey and the data was analysed with a bivariate and multivariate method in the statistic programme SPSS. The result of the study show that all three types of posts are important to use if companies publish posts on social media. The study contributes with knowledge of informative, personal and entertaining post and what effect they have on brand trust and brand loyalty. Informative and personal types of post have a significant and positive effect on brand trust. Brand loyalty is affected by all three types of post and the effects is positive. / Hur och vad företag publicerar på sociala medier har blivit allt viktigare. Olika typer av inlägg genererar olika effekter och vill företag skapa varumärkestillit och varumärkeslojalitet måste de ha detta i beaktande. Konsumenter vill bli nådda av innehåll som känns personligt och känna att företagen levererar något värdebringande. Innehållsmarknadsföring behandlar denna aspekt och fokuserar på att hjälpa, informera och underhålla mottagarna. Denna studie undersöker typerna av inlägg, informerande, personliga och underhållande och hur de påverkar varumärkestillit och varumärkeslojalitet. I studien har en kvantitativ metod använts och en enkätundersökning användes för att samla in data. 150 respondenter besvarade enkäten och data analyserades därefter med en bivariat analys samt multivariata analyser i statistikprogrammet SPSS. Studiens resultat visar att alla typerna av inlägg är viktiga att använda om företag publicerar inlägg på sociala medier. Studien bidrar med kunskap om vilka effekter informerande, personliga och underhållande inlägg har på varumärkestillit och varumärkeslojalitet. Informerande och personliga inlägg har en signifikant och en positiv effekt på varumärkestillit. När det gäller varumärkeslojalitet anses alla tre typerna av inlägg vara signifikanta samt att de har en positiv effekt på varumärkeslojalitet.

Made available in DSpace on 2017-07-24T19:22:08Z (GMT). No. of bitstreams: 1 Ana Paula Gebert.pdf: 9068136 bytes, checksum: 8f06dbf649af9345afc6e09a57f71fb6 (MD5) Previous issue date: 2008-02-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The aim is to analyze a non-linear mechanism of the cementation of root posts considering the existence of gaps in cement-dentin and cement-post interfaces analyzing the correlation of mechanical test and computational model. Were selected 15 mandibular pre-molars, to receive root posts Exacto (Angelus®/Londrina - Brazil) fixed with chemical resin cement Cement-Post (Angelus®/Londrina - Brazil). The teeth were termocycled, radiographed and cuted themselves getting cervical, middle and apical discs of roots. These discs were treated and molded with addition of silicone and epoxy resin replics was obtained before and after the compression test (220 N-0, 2 mm / min). The replics were analyzed in MEV to observe the formation of gaps at the interfaces on the upper surfaces of the specimens, which were measured in the Image Tool program. For statistical analysis of the comparison between the mensures of gaps (μm) in the interface was used in the Wilcoxon test which showed that there were statistical differences between groups (p <0.0001). In the comparison between the mensures of gaps in the same interface of the cervical, middle and apical discs before and after the compression test, there was no statistically significant difference (p = 0.4304) and (p = 0.7766), respectively. In cement-post interface there was no gaps in most specimens. The dentin discs were photographed and their images obtained from three-dimensional models simulating the compression test using the Finite Elements Method, considering linear-elastic material with values of module of elasticity and Poisson's coefficient, and obtained in the mechanical test of the traction, compression and bending resistance in the post and/or the cement. There was the Poisson's effect and a low stress concentration in dentin-cement and cement-post interfaces promoted by the force application, geometry and materials properties. In assessing the match of the mechanical test with the computational model, met a difference because of the consideration of perfect adhesion in computational model of the cervical and middle discs, which does not occur clinically, as there was formation of gaps in some root regions of the dentin discs. The apical discs were modeled like non-linear and it was considered an area of contact between the faces. / O objetivo é analisar de forma não-linear o mecanismo de cimentação de pinos intra-radiculares considerando a existência das fendas nas interfaces dentina-cimento-pino analisando a correspondência do ensaio mecânico e modelo computacional. Foram selecionados 15 pré-molares inferiores, para receber pinos intra-radiculares Exacto (Angelus®/Londrina - Brasil) fixados com cimento resinoso autopolimerizável Cement-Post (Angelus®/Londrina - Brasil). Os dentes foram termociclados, radiografados e cortados obtendo-se discos cervicais, médios e apicais das raízes. Esses discos foram tratados e moldados com silicone de adição e obtidas réplicas de resina epoxi antes e após o ensaio de compressão (220 N-0,2 mm/min). As réplicas foram analisadas em MEV para observar a formação de fendas nas interfaces nas faces superiores dos espécimes, as quais foram medidas no programa Image Tool. Para análise estatística da comparação entre as medidas de fendas (μm) na interface foi utilizado o teste Wilcoxon que demonstrou que houve diferenças estatísticas entre os grupos (p < 0,0001). Na comparação entre as medidas de fendas da mesma interface dos discos cervical, médio e apical antes e depois do ensaio de compressão, não houve diferenças significantes estatisticamente (p = 0,4304) e (p = 0,7766), respectivamente. Na interface cimento-pino observou-se ausência de fendas na maior parte dos espécimes. Os discos de dentina foram fotografados e a partir de suas imagens obtidos modelos tri-dimensionais analisados simulando-se o ensaio de compressão por meio do Método dos Elementos Finitos, considerando material elástico-linear com valores de módulo de elasticidade e Coeficiente de Poisson e, obtidos de ensaios mecânicos de resistência à tração, compressão e flexão realizados no pino e/ou no cimento. Observou-se o efeito Poisson e que houve uma concentração leve de tensões nas interfaces dentina-cimento e cimento-pino promovidas pela forma de aplicação da força, geometria e propriedades dos materiais. Na avaliação da correspondência do ensaio mecânico com o modelo computacional, encontrou-se uma diferença devido à consideração de adesão perfeita no modelo computacional dos discos cervicais e médios, o que não ocorre clinicamente, visto que houve formação de fendas em algumas regiões radiculares dos discos de dentina. Os discos apicais foram modelados de maneira não-linear, considerando-se uma superfície de contato entre as faces.

Submitted by Franciele Moreira (francielemoreyra@gmail.com) on 2017-09-12T18:31:43Z No. of bitstreams: 2 Dissertação - Lucas Floriano de Oliveira - 2017.pdf: 5617157 bytes, checksum: 2f2ed9775d7d1413b376e1c49c9891cf (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-09-19T13:50:57Z (GMT) No. of bitstreams: 2 Dissertação - Lucas Floriano de Oliveira - 2017.pdf: 5617157 bytes, checksum: 2f2ed9775d7d1413b376e1c49c9891cf (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-09-19T13:50:57Z (GMT). No. of bitstreams: 2 Dissertação - Lucas Floriano de Oliveira - 2017.pdf: 5617157 bytes, checksum: 2f2ed9775d7d1413b376e1c49c9891cf (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-08-18 / The objective of this research is to understand how the teaching of Portuguese for the deaf is being discussed by users of Portuguese blogs for the deaf, in which linguistic analyzes will be carried out under the Systemic-Functional Grammar. The research is of the qualitative-interpretative type and blogs have been used where tips on how to teach the Portuguese language to these students. Studies on the area of deafness showed that the Brazilian Sign Language(Libras) should be the first language to be acquired by the deaf, to further assist them in learning Portuguese as L2 or second language, in writing mode. The Systemic Functional Grammar is analyzed over Appraisal through the Portuguese language teaching blogs for the deaf by the GSF Attitude System applied in the comments of the participants of the posts of blogs who are professionals in teaching Portuguese to deaf people. Technological advances provide efficiency and convenience in the teaching-learning process of the Portuguese language through the use of blogs as a tool. We conclude that the blog advantage is favoring bilingualism and can be accessed in two languages or more. Thus, both Libras and Portuguese can help the deaf learning process, and they have also space for images which support the linguistic transcription of both languages. / O objetivo desta pesquisa é compreender como o ensino de português para surdos vem sendo discutido por usuários de blogs de Língua Portuguesa para surdos, em que se farão análises linguísticas com base no Sistema de Avaliatividade no âmbito da Gramática Sistêmico-Funcional. A pesquisa é do tipo quanti-qualitativa e foram utilizados textos de postagens em blogs onde se encontram dicas de como ensinar a Língua Portuguesa a esses estudantes. Estudos sobre a área da surdez mostraram que a Língua Brasileira de Sinais (Libras) deve ser a Primeira Língua a ser adquirida pelos surdos, para posteriormente auxiliá-los no aprendizado da Língua Portuguesa como L2 ou Segunda Língua, na modalidade escrita. A Gramática Sistêmico-Funcional é analisada pelo Sistema de Avaliatividade, nos posts de blogs de ensino da Língua Portuguesa para surdos, por intermédio do Sistema de Atitude da GSF aplicado nos comentários dos usuários dos blogs que são profissionais da área de ensino de português para surdos. Os avanços tecnológicos vêm proporcionando maior eficiência e praticidade no processo ensino-aprendizagem da Língua Portuguesa para surdos e os blogs são uma das ferramentas utilizadas. Percebe-se que uma das vantagens do blog é que favorece o Bilinguismo, podendo ser acessado nas duas línguas. Neste caso, a Libras e o português auxiliando o processo de aprendizagem do surdo, tendo espaço também para imagens que servem de apoio na transcrição linguística de ambas línguas.

Diseases involving fibrosis cause tens of thousands of deaths per year in the US alone. These diseases are characterized by a large amount of extracellular matrix, causing stiff abnormal tissues that may not function correctly. To take steps towards curing these diseases, a fundamental understanding of how cells interact with their substrate and how mechanical forces alter signaling pathways is vital. Studying the mechanobiology of cells and the interaction between a cell and its extracellular matrix can help explain the mechanisms behind stem cell differentiation, cell migration, and metastasis. Due to the correlation between force, extracellular matrix assembly, and substrate stiffness, it is vital to make in vitro models that more accurately simulate biological stiffness as well as measure the amount of force and extracellular matrix assembly. To accomplish this, blends of two types of poly(dimethylsiloxane) (PDMS) were made and the material properties of these polymer blends were characterized. A field of 5µm or 7µm microscopic pillars (referred to as posts) with a diameter of 2.2µm were fabricated from these blends. Each combination of PDMS blend and post height were calibrated and the stiffness was recorded. Additionally, polymer attachment experiments were run to ensure cells survived and had a normal phenotype on the different blends of PDMS when compared to pure PDMS. Finally, cells were placed onto a field of posts and their forces were calculated using the new stiffness found for each blend of post. Varying the PDMS material stiffness using blends allow posts to be much more physiologically relevant and help to create more accurate in vitro models while still allowing easy and accurate force measurement. More biologically relevant in vitro models can help us acquire more accurate results when testing new drugs or examining new signaling pathways.

Title: Comparison of body composition of soccer players according to their players' post Objectives: The main objective of this work is to determine the body composition of soccer players according to their post and to compare these data with the results of similar testing taken in foreign countries. Methods: 45 players participated in the testing in total. The machine of bioelectrical impedance BIA 2000 M was used for the detection of the body composition and the gained data were further proceeded in the programme NUTRI 4. The observed parameters were a percentage of body fat, an absolute amount of fat mass, fat-free and intracellular tissue. For the process of the statistic data (arithmetic average, BMI, standard deviation, tables and graphs) the programme Microsoft Excel 2007 was used. Results: The players of both Czech clubs have a typical body composition for top athletes. It was found out that the goalkeepers have the highest percentage of body fat out of all measured players. Defenders were proved to have the least percentage of body fat among all the measured players. Keywords: Soccer, player posts, body composition, bio impedance

Este trabalho teve como objetivo avaliar a microdureza de dois cimentos resinosos de polimerização dual (RelyX U100®, 3M-ESPE e Panavia F 2.0®, Kuraray), empregados na cimentação de pinos de fibra de vidro (Fibrekor-Jeneric® Pentron) variando o modo de polimerização em químico, fotoativação imediata ou tardia após 5min através de luz halógena, avaliando também o efeito do armazenamento em água deionizada por três meses. Este trabalho testou as seguintes hipóteses nulas: não há diferença nos valores de microdureza entre os cimentos, modo de polimerização, efeito do armazenamento e entre os terços radiculares. Sessenta raízes de incisivos bovinos, com 16mm de comprimento cérvico-apical, tiveram seus condutos obturados e, posteriormente, preparados para cimentação do pino intracanal. Os espécimes foram divididos em 6 grupos (n = 10), cada um subdividido em 2 subgrupos com 5 espécimes para cada cimento. Os pinos foram cimentados de acordo com o protocolo descrito por cada fabricante. No grupo A1, os espécimes foram mantidos em ambiente à prova de luz para que ocorresse apenas a polimerização química. No grupo B1, os espécimes foram cimentados e submetidos à fotoativação imediata, e, no grupo C1, realizou-se a fotoativação após 5 minutos. As raízes foram seccionadas longitudinalmente, para que a linha de cimento pudesse ser exposta e os testes de microdureza realizados. Após 7 dias, as médias de microdureza (± desvio padrão) foram obtidas, para os terços cervical, médio e apical, respectivamente: A1 (Panavia) - 41,25 ±3,38 / 38,17±1,74 / 35,63±1,73; A1 (U100) - 59,43±4,32 / 52,14±3,00 / 50,27±4,13; B1 (Panavia) - 75,29±4,84 / 60,36±6,76 / 48,97±3,33; B1 (U100) 62,41±6,83 / 53,99±4,74 / 49,04±2,20; C1 (Panavia) - 70,22±93 / 61,00±4,48 / 56,46±7,51; C1 (U100) - 62,40±6,66 / 53,69±2,00 / 51,54±2,18. Para os grupos armazenados em água, os valores médios de microdureza (± desvio padrão) obtidos nos 3 grupos, químico (grupo A2), fotoativado imediatamente (grupo B2) e fotoativado tardiamente (grupo C2), nos terços cervical, médio e apical, respectivamente, foram: A2 (Panavia) - 37,17±1,38 / 35,01±0,74 / 34,10±2,37; A2 (U100) - 52,39±2,00 / 52,13±3,01 / 51,06±1,48; B2 (Panavia) - 63,01±2,17 / 55,94±2,10 / 48,55±1,62; B2 (U100) - 58,81±2,34 / 55,19±1,42 / 55,71±3,17; C2 (Panavia) - 56,99±1,21 / 51,29±1,81 / 48,29±3,00; C2 (U100) - 59,02±2,04 / 57,05±2,04 / 54,95±1,05. Os resultados foram submetidos ao teste ANOVA a 4 critérios (cimento, modo de polimerização, armazenamento e terços), que detectou diferenças estatísticas entre os grupos, e o teste de Tukey foi aplicado para comparações individuais. Os resultados mostraram que: a fotoativação com luz halógena promoveu um aumento significativo nos valores de microdureza para o cimento Panavia; o armaz namento em água por três meses reduziu os valores de microdureza para a maioria dos grupos, sendo que o cimento o U100 apresentou menor variação de dureza quando comparado ao Panavia; os terços que receberam maior intensidade de luz halógena tiveram maior aumento de microdureza para ambos os cimentos, especialmente para o cimento Panavia. Conclui-se, portanto, que as hipóteses de nulidade propostas foram rejeitadas. / The objective of this study was to evaluate the microhardness of two dual cure resin cements (RelyX - U100®, 3M-ESPE and Panavia F 2.0®, Kuraray), used for fiberglass posts (Fibrekor ® - Jeneric Pentron) cementation. Chemical cure and a halogen immediate and late light cure source were compared, and the effect of storage in deionized water for three months was also evaluated. This study tested the following null hypotheses: there is no difference between the microhardness values for each dual cure resin cement, cure source type, storage time, or root thirds. Sixty bovine incisor roots 16mm long had their roots restored and then prepared for post cementation. The specimens were divided into 6 groups (n = 10), and each group was subdivided into 2 subgroups with 5 specimens for each cement. The posts were cemented according to manufacturers instructions. In group A1, the specimens were kept in a light-proof environment to ensure only a chemical cure. In group B1, the specimens were restored and subjected to immediate light curing, and in group C1, light curing was performed after 5 minutes. The roots were longitudinally sectioned to expose the cement line and perform microhardness tests. After 7 days, the average microhardness (± standard deviation) values were obtained for the cervical, medium and apical thirds, respectively: A1 (Panavia ) - 41,25±3,38 / 38,17±1,74 / 35,63±1,73; A1 (U100) - 59,43±4,32 / 52,14±3,00 / 50,27±4,13; B1 (Panavia) - 75,29±4,84 / 60,36±6,76 / 48,97±3,33; B1 (U100) - 62,41±6,83 / 53,99±4,74 / 49,04±2,20; C1 (Panavia) - 70,22±1,93 / 61,00±4,48 / 56,46±7,51; C1 (U100) - 62,40±6,66 / 53,69±2,00 / 51,54±2,18. For the 3 groups stored in deionized water (chemical [group A2], immediate light curing [group B2] and late light curing [group C2]), the average microhardness values (± standard deviation) obtained for the cervical, medium and apical thirds, respectively were: A2 (Panavia) - 37,17±1,38 / 35,01±0,74 / 34,10±2,37; A2 (U100) - 52,39±2,00 / 52,13±3,01 / 51,06±1,48; B2 (Panavia) - 63,01±2,17 / 55,94±2,10 / 48,55±1,62; B2 (U100) - 58,81±2,34 / 55,19±1,42 / 55,71±3,17; C2 (Panavia) - 56,99±1,21 / 51,29±1,81 / 48,29±3,00; C2 (U100) - 59,02±2,04 / 57,05±2,04 / 54,95±1,05. ANOVA testing was used to detect statistical differences among the 4 criteria (cements, cure mode, storage and thirds) and the Tukey test was used for individual comparisons. The results showed that the halogen light cure promoted a significant increase in microhardness values for Panavia cement; storage in water for three months reduced microhardness values for most of the groups, although U100 resulted in less microhardness variation compared to Panavia; the thirds that received a higher intensity of halogen light had a higher increase in the average values of microhardness for both cements, especially for Panavia. Therefore, the null hypotheses proposed in this work were rejected.

A raspagem e o aplainamento radicular removem o cemento presente nesta área, o qual funcionaria como barreira de dentina contra a penetração de bactérias, toxinas e outros produtos vindos da superfície externa do dente. O objetivo deste estudo foi avaliar, in vitro, em dentes tratados endodonticamente, a resistência apresentada por diferentes materiais de cimentação na infiltração do azul de metileno, que poderia atravessar a dentina radicular, quando submetido a duas diferentes situações: a) raspagem e aplainamento do cemento radicular e b) remoção de cemento com pontas diamantadas. Para isso, utilizou-se 48 dentes humanos unirradiculares, cedidos pelo banco de dentes da FOUSP, tratados endodonticamente e preparados para receberem pinos. Estes foram modelados com resina acrílica para que, por meio de fundição, fossem obtidos os retentores intrarradiculares metálicos. Os dentes foram divididos em 4 grupos com 12 espécimes, e a cada um dos grupos, destinado um tipo de material diferente para a cimentação: Cimento de Zinco® (SS White, Rio de Janeiro, Rio de Janeiro, Brasil), Cimentos resinosos Panavia F® (Kuraray, Kurashiki, Okayama, Japan), Rely X U 100® (3M Dental, Seefeld, Alemanha) e Rely X Luting 2® (3M Dental, Sant Paul, Estados Unidos). Após esse procedimento, delimitaram-se duas janelas na região cervical da raiz, sendo que num dos lados o cemento foi removido com uma ponta diamantada e no lado oposto, com 40 golpes de cureta Gracey 5-6 (Neumar, São Paulo, São Paulo, Brasil) paralelos ao longo eixo do dente. Exceto nas regiões instrumentadas, o dente foi impermeabilizado externamente e exposto à solução de azul de metileno a 1% e pH 7,2 durante 48 horas. As amostras foram desgastadas no sentido do longo eixo até o maior diâmetro do pino e a área impregnada pelo corante foi digitalizada e mensurada com o programa Imagelab®. A comparação da área impregnada pelo agente traçador na película dos cimentos, nos terços cervical e médio, revelou diferenças estatisticamente significantes entre si (p < 0,05). No lado em que a dentina foi removida com broca, houve diferença estatisticamente significante quando os três materiais adesivos foram comparados com o Cimento de Zinco (SS White, Rio de Janeiro, Rio de Janeiro, Brasil). Na comparação entre os cimentos resinosos houve diferença estatisticamente significante (p<05) somente entre os cimentos Panavia F® (Kuraray, Kurashiki, Okayama, Japan) e Rely X U 100® (3M Dental, Seefeld, Alemanha) para o terço apical. Na superfície tratada com curetas periodontais, verificou-se diferença estatisticamente significante entre os grupos estudados (p < 0,05) apenas quando comparados o cimento Rely X U 100® (3M Dental, Seefeld, Alemanha) com Rely X Luting 2® (3M Dental, Sant Paul, Estados Unidos) para o terço cervical. Concluiu-se que para o tratamento com ponta diamantada, que os cimentos Panavia F® (Kuraray, Kurashiki, Okayama, Japan), Rely X U 100® (3M Dental, Seefeld, Alemanha) e Rely X Luting 2® (3M Dental, Sant Paul, Estados Unidos) têm comportamento semelhante para os terços cervical e médio, diferindo apenas no terço apical. Já para o tratamento com curetas periodontais, os cimentos Panavia F® (Kuraray, Kurashiki, Okayama, Japan), Rely X U 100® (3M Dental, Seefeld, Alemanha) e Rely X Luting 2® (3M Dental, Sant Paul, Estados Unidos) mostraram resultados similares para os terços médio e apical, diferindo apenas no terço cervical. / Scaling and root planning remove cementum present in this area, which would acts as a dentin barrier against penetration of bacterias, toxins and other products coming from the surface of the tooth. The objective of this study was to evaluate in vitro endodontically treated teeth, the resistance of different materials to methylene blue, which could cross the root dentin when submitted to two different situations: a) scaling and root planning b) removal of cementum with drills. It was used 48 human uniradicular teeth, assigned by FOUSPs teeth bank and were endodontically treated and prepared to receive pins. These were modeled with an acrylic resin in order to obtain the metallic intraradicular posts. The teeth were divided into four groups with twelve specimens. Each one of the groups received a different material for cementing: Cement of Zinc® (SS White, Rio de Janeiro, Rio de Janeiro, Brazil), Panavia F® Resin Cements (Kuraray, Kurashiki, Okayama, Japan), Rely X U 100® (3M Dental, Seefeld, Germany) and Rely X Luting 2® (3M Dental, Sant Paul, United States). After this procedure, it was delimited two windows in the cervical region of the root. One of the sides the cementum was removed with a diamond drill and on the other side, with 40 Gracey 5-6 curette strokes (Neumar, São Paulo, Brazil) parallel to the long axis of the tooth. Except on the instrumented regions, the tooth was externally sealed and exposed to a 1% methylen blue solution and pH 7.2 during 48 hours. The samples were scraped from the long axis until the largest post diameter. The impregnated area with the dye were scanned and measured with the Imagelab® program. The comparison between the impregnated area through the tracer agent on the cement film in the cervical and medium thirds revealed statistically significant differences (p<0,05). On the side where the dentin was removed with a drill, there was a statistically significant difference when the three adhesive materials were compared to the Zinc Cement (SS White, Rio de Janeiro, Rio de Janeiro, Brazil). In the comparison between the resin cements there was a statistically significant difference (p<0,05) only between the cements: Panavia F® (Kuraray, Kurashiki, Okayama, Japan) and Rely X U 100® (3M Dental, Seefeld, Germany) for the apical third. On the surface treated with periodontal curettes, it was identified a meaningful statistical difference between the studied groups (p<0,05) only when compared the cements: Rely X U 100® (3M Dental, Seefeld, Germany) with Rely X Luting 2® (3M Dental, Sant Paul, United States) for the cervical third. The conclusion was that when the treatment uses a drill, the cements: Panavia F® (Kuraray, Kurashiki, Okayama, Japan), Rely X U 100® (3M Dental, Seefeld, Germany) and Rely X Luting 2® (3M Dental, Sant Paul, United States) have similar behavior to the cervical and medium third. The unique difference comes from the apical third. On the other hand, the treatments using periodontal curettes, the cements Panavia F® (Kuraray, Kurashiki, Okayama, Japan), Rely X U 100® (3M Dental, Seefeld, Germany) and Rely X Luting 2® (3M Dental, Sant Paul, United States) resulted in similar results for the medium and apical thirds, only differing on the cervical third.

O objetivo deste estudo foi avaliar, in vitro, a resistência de união de retentores intrarradiculares previamente irradiada com laser de diodo em alta intensidade (&lambda;= 830 nm), tanto em regime contínuo como pulsado. Foram utilizados retentores intrarradiculares metálicos ou de fibra de vidro, cimentados com fosfato de zinco ou cimento resinoso auto-condicionante. Assim, as variáveis analisadas foram o regime de irradiação, o tipo de retentor intrarradicular e o tipo de agente cimentante na resistência de união. Estas variáveis foram analisadas, in vitro, nos 3 terços radiculares (cervical, médio e apical) de 90 dentes humanos endodonticamente tratados, preparados para receber retentor intrarradicular e irradiados com laser de diodo em alta intensidade (830 nm). Após a irradiação os retentores foram cimentados com cimento de fosfato de zinco ou com cimento resinoso autocondicionante. As raízes foram seccionadas por meio de cortes transversais dos terços cervical, médio e apical, obtendo-se, assim, seis amostras de cada raiz. Cada uma das amostras foi submetida ao ensaio de resistência de união de maneira cega. Conclui-se que a resistência mecânica à compressão de retentores intrarradiculares em dentina previamente irradiada com laser de diodo de alta intensidade (&lambda;= 830 nm) apresentou maiores valores na dentina intrarradicular tanto no regime contínuo como pulsado, sendo ligeiramente superior no regime pulsado. Foi possível verificar que, nos terços médio e cervical, a irradiação com laser de diodo pulsado (Pm = 1 W, I = 994 W/cm2) resultou em maiores valores de resistência de união, com ambos os cimentos e ambos os tipos de núcleo. Houve diferença estatisticamente significante nos valores de união nos diferentes terços dos grupos tratados, sendo superior para o terço cervical (p < 0,05). Assim, a técnica de irradiação do conduto com laser de diodo mostrou-se eficaz no aumento da resistência de união de retentores intrarradiculares. / The aim of this study was to evaluate, in vitro, the bond strength of intracanal post cemented on irradiated dentin by a high intensity diode laser (&lambda; = 830 nm), both continuous and pulsed regime. Metal or fiber glass posts were used and cemented with zinc phosphate cement or self-etching resin-based cement. Thus, the variables analyzed were the regime of irradiation, the type of post and type of luting agent on bond strength. These variables were analyzed in vitro the 3 root thirds (cervical, middle and apical) of 90 endodontically treated human teeth prepared to receive posts and irradiated with diode laser at high intensity (830 nm). After irradiation, posts were cemented with zinc phosphate or self-etching resin cement. The roots were transversely in the cervical, middle and apical thirds, resulting in six samples each root. Each sample was subjected to the test of bond strength blindly. We concluded that the mechanical strength of intracanal posts cemented on dentin irradiated by high intensity diode laser (&lambda; = 830 nm) showed higher adhesion values in dentin, both for continuous and pulsed regime, being slightly higher in the pulsed regime. It was possible to verify that in the cervical and middle thirds, irradiation with pulsed diode laser (Pm = 1 W, I = 994 W/cm2) resulted in higher bond strength using both cements and both types posts. There was a significant difference among the different thirds of the treated groups, being higher for the cervical third (p < 0,05). So, irradiation with diode laser was effective to increase the resistence of union of intrarradicular posts.

O objetivo deste estudo foi avaliar, in vitro, a resistência de união de retentores intrarradiculares previamente irradiada com laser de diodo em alta intensidade (&lambda;= 830 nm), tanto em regime contínuo como pulsado. Foram utilizados retentores intrarradiculares metálicos ou de fibra de vidro, cimentados com fosfato de zinco ou cimento resinoso auto-condicionante. Assim, as variáveis analisadas foram o regime de irradiação, o tipo de retentor intrarradicular e o tipo de agente cimentante na resistência de união. Estas variáveis foram analisadas, in vitro, nos 3 terços radiculares (cervical, médio e apical) de 90 dentes humanos endodonticamente tratados, preparados para receber retentor intrarradicular e irradiados com laser de diodo em alta intensidade (830 nm). Após a irradiação os retentores foram cimentados com cimento de fosfato de zinco ou com cimento resinoso autocondicionante. As raízes foram seccionadas por meio de cortes transversais dos terços cervical, médio e apical, obtendo-se, assim, seis amostras de cada raiz. Cada uma das amostras foi submetida ao ensaio de resistência de união de maneira cega. Conclui-se que a resistência mecânica à compressão de retentores intrarradiculares em dentina previamente irradiada com laser de diodo de alta intensidade (&lambda;= 830 nm) apresentou maiores valores na dentina intrarradicular tanto no regime contínuo como pulsado, sendo ligeiramente superior no regime pulsado. Foi possível verificar que, nos terços médio e cervical, a irradiação com laser de diodo pulsado (Pm = 1 W, I = 994 W/cm2) resultou em maiores valores de resistência de união, com ambos os cimentos e ambos os tipos de núcleo. Houve diferença estatisticamente significante nos valores de união nos diferentes terços dos grupos tratados, sendo superior para o terço cervical (p < 0,05). Assim, a técnica de irradiação do conduto com laser de diodo mostrou-se eficaz no aumento da resistência de união de retentores intrarradiculares. / The aim of this study was to evaluate, in vitro, the bond strength of intracanal post cemented on irradiated dentin by a high intensity diode laser (&lambda; = 830 nm), both continuous and pulsed regime. Metal or fiber glass posts were used and cemented with zinc phosphate cement or self-etching resin-based cement. Thus, the variables analyzed were the regime of irradiation, the type of post and type of luting agent on bond strength. These variables were analyzed in vitro the 3 root thirds (cervical, middle and apical) of 90 endodontically treated human teeth prepared to receive posts and irradiated with diode laser at high intensity (830 nm). After irradiation, posts were cemented with zinc phosphate or self-etching resin cement. The roots were transversely in the cervical, middle and apical thirds, resulting in six samples each root. Each sample was subjected to the test of bond strength blindly. We concluded that the mechanical strength of intracanal posts cemented on dentin irradiated by high intensity diode laser (&lambda; = 830 nm) showed higher adhesion values in dentin, both for continuous and pulsed regime, being slightly higher in the pulsed regime. It was possible to verify that in the cervical and middle thirds, irradiation with pulsed diode laser (Pm = 1 W, I = 994 W/cm2) resulted in higher bond strength using both cements and both types posts. There was a significant difference among the different thirds of the treated groups, being higher for the cervical third (p < 0,05). So, irradiation with diode laser was effective to increase the resistence of union of intrarradicular posts.